1. Field
Embodiments relate to light sensor circuits, driving methods thereof, and light sensitive type touch screen panels employing a light sensor circuit as a sensor cell.
2. Description of the Related Art
Flat panel display devices include, e.g., organic light emitting display devices, liquid crystal display devices, plasma, display devices, field emission display devices, etc. In general, flat panel display devices are advantageous relative to conventional cathode ray tube (CRT) devices.
More particularly, in general, flat panel display devices are thinner in thickness, lighter in weight, and adapted to consume less power than the conventional CRT devices. Flat panel display devices, e.g., organic light emitting display devices or liquid crystal display devices, may also be employed in portable electronic equipment as they may be easily manufactured in a small size and/or may be employed for a relatively long time with battery power.
More particularly, many devices may employ a touch screen panel by which a user may input his or her instruction by selecting among instruction contents displayed on the screen of the flat panel display device using, e.g., a human hand or an object. The touch screen panel may be provided on a front face of the flat panel display device and may serve to convert a contact position directly contacted by human hand or the object into electrical signals so that the instruction contents selected at the contact position may be accepted as input signals.
A separate input device, such as a keyboard and/or mouse, which may generally be coupled to the flat panel display device, may be replaced by a touch screen panel that may be adapted to carry out additional functions. There are various types of touch screen panels, e.g., resistive type panels, capacitive type panels, light sensitive type panels.
Resistive type panels may operate based on a resistive connection between transparent conductive films that are arranged between two substrates. Such resistive type panels may be advantageous in that they are relatively easy to implement, but may be disadvantages in that mechanical and environmental reliability may be relatively low.
Capacitive type panels may determine a contact position of by sensing fine current flowing between a sensor electrode and a finger according to a change in capacitance. Such capacitive technology may be disadvantageous in that it may be more vulnerable to noise signals.
Light sensitive type panels do not employ a film, etc., and may fundamentally recognize a touch based on, e.g., high transmittance. Further, maintenance of the transmittance and brightness of the display device may be important factors for providing high quality devices.
However, more devices and/or methods adapted for more precise light sensing may be advantageous and/or required in order to implement the light sensitive type touch screen panel as described above.